Investments (Tables)

12 Months Ended

Jan. 31, 2019

As of January 31, 2019, debt securities consisted of the following (in thousands):



	Amortized Cost		Unrealized Gains		Unrealized Losses			Aggregate Fair Value
U.S. treasury securities	$	396,347	$	61	$	(178	)	$	396,230
U.S. agency obligations	241,914		73		(151		)	241,836
Corporate bonds	419,784		336		(352		)	419,768
Commercial paper	254,175		—		(2		)	254,173
	$	1,312,220	$	470	$	(683	)	$	1,312,007
Included in cash and cash equivalents	$	216,270	$	—	$	—		$	216,270
Included in marketable securities	$	1,095,950	$	470	$	(683	)	$	1,095,737

As of January 31, 2018, debt securities consisted of the following (in thousands):



	Amortized Cost		Unrealized Gains		Unrealized Losses			Aggregate Fair Value
U.S. treasury securities	$	797,977	$	—	$	(1,142	)	$	796,835
U.S. agency obligations	683,551		—		(1,127		)	682,424
Corporate bonds	470,259		16		(1,154		)	469,121
Commercial paper	602,727		—		—			602,727
	$	2,554,514	$	16	$	(3,423	)	$	2,551,107
Included in cash and cash equivalents	$	417,613	$	—	$	(1	)	$	417,612
Included in marketable securities	$	2,136,901	$	16	$	(3,422	)	$	2,133,495

Equity investments consisted of the following (in thousands):



		January 31,
	Consolidated Balance Sheets Location	2019		2018
Money market funds	Cash and cash equivalents	$	237,071	$	551,804
Marketable equity investments	Marketable securities	44,127		—
Non-marketable equity investments	Other assets	36,925		28,005
		$	318,123	$	579,809

Realized and unrealized gains and losses associated with our equity investments consisted of the following (in thousands):



	Year Ended January 31,
	2019		2018			2017
Net realized gains (losses) recognized on equity investments sold	$	8,333	$	720		$	65
Net unrealized gains (losses) recognized on equity investments held	32,127		(692		)	(15,000		)
Total net gains (losses) recognized in other income (expense), net	$	40,460	$	28		$	(14,935	)